Difference Between Solution and Suspension

In the natural environment, most of the substances exist as mixtures (E.g. air, water). In a mixture, there are two or more substances, but they are not chemically joined with each other. Mixtures show different physical or chemical properties than the individual substances. Solutions, suspensions, and colloids are examples for mixtures.

Solution

A solution is a homogeneous mixture of two or more substances. It is called a homogenous mixture, because the composition is uniform throughout the solution. The components of a solution are mainly of two types, solutes and the solvent. Solvent dissolves the solutes and form a uniform solution. So, normally solvent amount is higher than the solute quantity. All the particles in a solution have the size of a molecule or an ion, so they cannot be seen by the naked eye. The solutions can have a color if the solvent or the solutes can absorb visible light. However, solutions are typically transparent. Solvents can be in a liquid, gaseous or solid state. Most common solvents are liquids. Among liquids, water is considered as a universal solvent, because it can dissolve many substances than any other solvent. Gas, solid or any other liquid solute can be dissolved in liquid solvents. In gas solvents, only gas solutes can be dissolved. There is a limit to the amount of solutes that can be added to a certain amount of solvent. The solution is said to be saturated if the maximum amount of the solute is added to the solvent. If there is a very low amount of solutes, the solution is diluted, and if there is a high amount of solutes in the solution, it is a concentrated solution. By measuring the concentration of a solution, we can get an idea about the amount of solutes in the solution.

Suspension

Suspension is a heterogeneous mixture of substances (E.g.: muddy water). There are two components in the suspension, the dispersed material and the dispersion medium. There are larger solid particles (dispersed material) distributed in a dispersion medium. The medium can be a liquid, gas or a solid. However, if the suspension is allowed to stand still for some time, the particles can be settled down to the bottom. By mixing it, the suspension can be formed again. The particles in the suspension are visible to the naked eye, and through filtration, they can be separated. Because of the larger particles, the suspensions tend to be opaque, and not transparent.

- The solute particles in a solution are in the size of a molecule or an ion, but the particles in suspensions are larger than that. Therefore, particles in a solution are not visible to the naked eye, and particles in suspensions may be visible.

- Usually solutions are transparent, and suspensions are opaque.

- The components in a solvent do not separate on standing, but in suspensions, particles will settle if it is left undisturbed.

- The particles in a suspension can be filtered out, but the particles in a solution can’t.